aboutsummaryrefslogtreecommitdiffstats
path: root/kernel
Commit message (Collapse)AuthorAge
* blktrace: fix the original blktraceLi Zefan2009-03-31
| | | | | | | | | | | | | | | | | | | | | | | Currently the original blktrace, which is using relay and is used via ioctl, is broken. You can use ftrace to see the output of blktrace, but user-space blktrace is unusable. It's broken by "blktrace: add ftrace plugin" (c71a896154119f4ca9e89d6078f5f63ad60ef199) - if (unlikely(bt->trace_state != Blktrace_running)) + if (unlikely(bt->trace_state != Blktrace_running || !blk_tracer_enabled)) return; With this patch, both ioctl and ftrace can be used, but of course you can't use both of them at the same time. Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Acked-by: Jens Axboe <jens.axboe@oracle.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* blktrace: fix a race when creating blk_tree_root in debugfsLi Zefan2009-03-31
| | | | | | | | | | | | | | | | | | | | | | t1 t2 ------ ------ do_blk_trace_setup() do_blk_trace_setup() if (!blk_tree_root) { if (!blk_tree_root) blk_tree_root = create_dir() blk_tree_root = create_dir(); (now blk_tree_root == NULL) ... dir = create_dir(name, blk_tree_root); Due to this race, t1 will create 'dir' in /debugfs but not /debugfs/block. Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Acked-by: Jens Axboe <jens.axboe@oracle.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* blktrace: fix timestamp in binary outputLi Zefan2009-03-31
| | | | | | | | | | | | | | | | | | | | | I found the timestamp is wrong: # echo bin > trace_option # echo blk > current_tracer # cat trace_pipe | blkparse -i - 8,0 0 0 0.000000000 504 A W ... ... 8,7 1 0 0.008534097 0 C R ... (should be 8.534097xxx) user-space blkparse expects the timestamp to be nanosecond. Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Acked-by: Jens Axboe <jens.axboe@oracle.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* blktrace: print human-readable act_maskLi Zefan2009-03-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: new feature, allow symbolic values in /debug/tracing/act_mask Print stringified act_mask instead of hex value: # cat act_mask read,write,barrier,sync,queue,requeue,issue,complete,fs,pc,ahead,meta, discard,drv_data # echo "meta,write" > act_mask # cat act_mask write,meta Also: - make act_mask accept "ahead", "meta", "discard" and "drv_data" - use strsep() instead of strchr() to parse user input - return -EINVAL if a token is not found in the mask map - fix a bug that 'value' is unsigned, so it can < 0 - propagate error value of blk_trace_mask2str() to userspace, but not always return -ENXIO. Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Acked-by: Jens Axboe <jens.axboe@oracle.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> LKML-Reference: <49C8AB42.1000802@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* blktrace: fix t_error()Li Zefan2009-03-24
| | | | | | | | | | | | | | Impact: fix error flag output t_error() should return t->error but not t->sector. Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Acked-by: Jens Axboe <jens.axboe@oracle.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> LKML-Reference: <49C8945F.5020802@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* blktrace: fix wrong calculation of RWBSLi Zefan2009-03-24
| | | | | | | | | | | | | | Impact: fix the output of IO type category characters Trace categories are the upper 16 bits, not the lower 16 bits. Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Acked-by: Jens Axboe <jens.axboe@oracle.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> LKML-Reference: <49C89432.8010805@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* blktrace: mark ddir_act[] constLi Zefan2009-03-24
| | | | | | | | | | | | | | Impact: cleanup ddir_act and what2act always stay immutable. Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Acked-by: Jens Axboe <jens.axboe@oracle.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> LKML-Reference: <49C89415.5080503@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* blktrace: avoid accessing NULL bdev->bd_diskLi Zefan2009-03-21
| | | | | | | | | | | | | | | | bdev->bd_disk can be NULL, if the block device is not opened. Try this against an unmounted partition, and you'll see NULL dereference: # echo 1 > /sys/block/sda/sda5/enable Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <49C30098.6080107@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* blktrace: remove sysfs_blk_trace_enable_show/store()Li Zefan2009-03-21
| | | | | | | | | | | | | sysfs_blk_trace_enable_show()/store() share most of code with sysfs_blk_trace_attr_show()/store(). Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <49C30EA3.1060004@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* blktrace: report EBUSY correctlyLi Zefan2009-03-21
| | | | | | | | | | | | | | | | | | | | | blk_trace_remove_queue() returns EINVAL if q->blk_trace == NULL, but blk_trace_setup_queue() doesn't return EBUSY if q->blk_trace != NULL. # echo 0 > sdaX/trace/enable # echo 0 > sdaX/trace/enable bash: echo: write error: Invalid argument # echo 1 > sdaX/trace/enable # echo 1 > sdaX/trace/enable (should return EBUSY) Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <49C2F614.2010101@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* blktrace: don't increase blk_probes_ref if failed to setup blk traceLi Zefan2009-03-21
| | | | | | | | | | | | | do_blk_trace_setup() may return EBUSY, but the current code doesn't decrease blk_probes_ref in this case. Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <49C2F5FF.80002@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* blktrace: remove blk_probe_mutexLi Zefan2009-03-21
| | | | | | | | | | | | | blk_register_tracepoints() always returns 0, so make it return void, thus we don't need to use blk_probe_mutex to protect blk_probes_ref. Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <49C2F5EA.8060606@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* blktrace: make blk_tracer_enabled a bool flagLi Zefan2009-03-21
| | | | | | | | | | | | It doesn't have to be a counter, and it can be a bool flag instead. Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Steven Rostedt <rostedt@goodmis.org> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> LKML-Reference: <49C2F5D3.8090104@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* blktrace: fix possible memory leakLi Zefan2009-03-21
| | | | | | | | | | | | | When we failed to create "block" debugfs dir, we should do some cleanups. Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <49C2F5B2.8000800@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
*---. Merge branches 'tracing/ftrace', 'tracing/kprobes', 'tracing/tasks' and ↵Ingo Molnar2009-03-20
|\ \ \ | | | | | | | | | | | | 'linus' into tracing/core
| | | * module: fix refptr allocation and release orderMasami Hiramatsu2009-03-17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: fix ref-after-free crash on failed module load Fix refptr bug: Change refptr allocation and release order not to access a module data structure pointed by 'mod' after freeing mod->module_core. This bug will cause kernel panic(e.g. failed to find undefined symbols). This bug was reported on systemtap bugzilla. http://sources.redhat.com/bugzilla/show_bug.cgi?id=9927 Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Cc: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
| | * | tracing: fix command line to pid reverse mapCarsten Emde2009-03-18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: fix command line to pid mapping map_cmdline_to_pid[] is checked in trace_save_cmdline(), but never updated. This results in stale pid to command line mappings and the tracer output will associate the wrong comm string. Signed-off-by: Carsten Emde <Carsten.Emde@osadl.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Steven Rostedt <srostedt@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> LKML-Reference: <new-submission> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| | * | tracing: fix trace_find_cmdline()Thomas Gleixner2009-03-18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: prevent stale command line output In case there is no valid command line mapping for a pid trace_find_cmdline() returns without updating the comm buffer. The trace dump keeps the previous entry which results in confusing trace output: <idle>-0 [000] 280.702056 .... <idle>-23456 [000] 280.702080 .... Update the comm buffer with "<...>" when no mapping is found. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Steven Rostedt <srostedt@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> LKML-Reference: <new-submission> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| | * | tracing: replace the crude (unsigned) -1 hackeryThomas Gleixner2009-03-18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: cleanup The command line recorder uses (unsigned) -1 to mark non mapped entries in the pid to command line maps. The validity check is completely unintuitive: idx >= SAVED_CMDLINES There is no need for such casting games. Use a constant to mark unmapped entries and check for that constant to make the code readable and understandable. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Steven Rostedt <srostedt@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> LKML-Reference: <new-submission> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| | * | tracing: stop command line recording when tracing is disabledThomas Gleixner2009-03-18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: prevent overwrite of command line entries When the tracer is stopped the command line recording continues to record. The check for tracing_is_on() is not sufficient here as the ringbuffer status is not affected by setting debug/tracing/tracing_enabled to 0. On a non idle system this can result in the loss of the command line information for the stopped trace, which makes the trace harder to read and analyse. Check tracer_enabled to allow further recording. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Steven Rostedt <srostedt@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> LKML-Reference: <new-submission> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | kprobes: Fix locking imbalance in kretprobesAnanth N Mavinakayanahalli2009-03-18
| |/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix locking imbalance in kretprobes: ===================================== [ BUG: bad unlock balance detected! ] ------------------------------------- kthreadd/2 is trying to release lock (&rp->lock) at: [<c06b3080>] pre_handler_kretprobe+0xea/0xf4 but there are no more locks to release! other info that might help us debug this: 1 lock held by kthreadd/2: #0: (rcu_read_lock){..--}, at: [<c06b2b24>] __atomic_notifier_call_chain+0x0/0x5a stack backtrace: Pid: 2, comm: kthreadd Not tainted 2.6.29-rc8 #1 Call Trace: [<c06ae498>] ? printk+0xf/0x17 [<c06b3080>] ? pre_handler_kretprobe+0xea/0xf4 [<c044ce6c>] print_unlock_inbalance_bug+0xc3/0xce [<c0444d4b>] ? clocksource_read+0x7/0xa [<c04450a4>] ? getnstimeofday+0x5f/0xf6 [<c044a9ca>] ? register_lock_class+0x17/0x293 [<c044b72c>] ? mark_lock+0x1e/0x30b [<c0448956>] ? tick_dev_program_event+0x4a/0xbc [<c0498100>] ? __slab_alloc+0xa5/0x415 [<c06b2fbe>] ? pre_handler_kretprobe+0x28/0xf4 [<c06b3080>] ? pre_handler_kretprobe+0xea/0xf4 [<c044cf1b>] lock_release_non_nested+0xa4/0x1a5 [<c06b3080>] ? pre_handler_kretprobe+0xea/0xf4 [<c044d15d>] lock_release+0x141/0x166 [<c06b07dd>] _spin_unlock_irqrestore+0x19/0x50 [<c06b3080>] pre_handler_kretprobe+0xea/0xf4 [<c06b20b5>] kprobe_exceptions_notify+0x1c9/0x43e [<c06b2b02>] notifier_call_chain+0x26/0x48 [<c06b2b5b>] __atomic_notifier_call_chain+0x37/0x5a [<c06b2b24>] ? __atomic_notifier_call_chain+0x0/0x5a [<c06b2b8a>] atomic_notifier_call_chain+0xc/0xe [<c0442d0d>] notify_die+0x2d/0x2f [<c06b0f9c>] do_int3+0x1f/0x71 [<c06b0e84>] int3+0x2c/0x34 [<c042d476>] ? do_fork+0x1/0x288 [<c040221b>] ? kernel_thread+0x71/0x79 [<c043ed1b>] ? kthread+0x0/0x60 [<c043ed1b>] ? kthread+0x0/0x60 [<c04040b8>] ? kernel_thread_helper+0x0/0x10 [<c043ec7f>] kthreadd+0xac/0x148 [<c043ebd3>] ? kthreadd+0x0/0x148 [<c04040bf>] kernel_thread_helper+0x7/0x10 Signed-off-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Tested-by: Bharata B Rao <bharata@linux.vnet.ibm.com> Cc: Masami Hiramatsu <mhiramat@redhat.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: <stable@kernel.org> [2.6.29.x, 2.6.28.x, 2.6.27.x] LKML-Reference: <20090318113621.GB4129@in.ibm.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | | tracing/ring-buffer: fix non cpu hotplug caseFrederic Weisbecker2009-03-19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: fix warning with irqsoff tracer The ring buffer allocates its buffers on pre-smp time (early_initcall). It means that, at first, only the boot cpu buffer is allocated and the ring-buffer cpumask only has the boot cpu set (cpu_online_mask). Later, the secondary cpu will show up and the ring-buffer will be notified about this event: the appropriate buffer will be allocated and the cpumask will be updated. Unfortunately, if !CONFIG_CPU_HOTPLUG, the ring-buffer will not be notified about the secondary cpus, meaning that the cpumask will have only the cpu boot set, and only one cpu buffer allocated. We fix that by using cpu_possible_mask if !CONFIG_CPU_HOTPLUG. This patch fixes the following warning with irqsoff tracer running: [ 169.317794] WARNING: at kernel/trace/trace.c:466 update_max_tr_single+0xcc/0xf3() [ 169.318002] Hardware name: AMILO Li 2727 [ 169.318002] Modules linked in: [ 169.318002] Pid: 5624, comm: bash Not tainted 2.6.29-rc8-tip-02636-g6aafa6c #11 [ 169.318002] Call Trace: [ 169.318002] [<ffffffff81036182>] warn_slowpath+0xea/0x13d [ 169.318002] [<ffffffff8100b9d6>] ? ftrace_call+0x5/0x2b [ 169.318002] [<ffffffff8100b9d6>] ? ftrace_call+0x5/0x2b [ 169.318002] [<ffffffff8100b9d1>] ? ftrace_call+0x0/0x2b [ 169.318002] [<ffffffff8101ef10>] ? ftrace_modify_code+0xa9/0x108 [ 169.318002] [<ffffffff8106e27f>] ? trace_hardirqs_off+0x25/0x27 [ 169.318002] [<ffffffff8149afe7>] ? _spin_unlock_irqrestore+0x1f/0x2d [ 169.318002] [<ffffffff81064f52>] ? ring_buffer_reset_cpu+0xf6/0xfb [ 169.318002] [<ffffffff8106637c>] ? ring_buffer_reset+0x36/0x48 [ 169.318002] [<ffffffff8106aeda>] update_max_tr_single+0xcc/0xf3 [ 169.318002] [<ffffffff8100bc17>] ? sysret_check+0x22/0x5d [ 169.318002] [<ffffffff8106e3ea>] stop_critical_timing+0x142/0x204 [ 169.318002] [<ffffffff8106e4cf>] trace_hardirqs_on_caller+0x23/0x25 [ 169.318002] [<ffffffff8149ac28>] trace_hardirqs_on_thunk+0x3a/0x3c [ 169.318002] [<ffffffff8100bc17>] ? sysret_check+0x22/0x5d [ 169.318002] ---[ end trace db76cbf775a750cf ]--- Because this tracer may try to swap two cpu ring buffers for an unregistered cpu on the ring buffer. This patch might also fix a fair loss of traces due to unallocated buffers for secondary cpus. Reported-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Acked-b: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1237470453-5427-1-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | | tracepoints: dont update zero-sized tracepoint sectionsIngo Molnar2009-03-18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Zero-sized tracepoint sections can occur if tracing is enabled but no tracepoint is defined. Do not emit a warning in that case. Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Jaswinder Singh Rajput <jaswinderrajput@gmail.com> LKML-Reference: <1237394936.3132.1.camel@localhost.localdomain> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | | tracing: fix oops in tracepoint_update_probe_range()Jaswinder Singh Rajput2009-03-18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Change this crash: BUG: unable to handle kernel NULL pointer dereference at (null) IP: [<ffffffff8107d4de>] tracepoint_update_probe_range+0x1f/0x9b PGD 13d5fb067 PUD 13d688067 PMD 0 Oops: 0000 [#1] SMP To a more debuggable WARN_ONCE(). Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1237394936.3132.1.camel@localhost.localdomain> [ moved the check outside the lock and added a WARN_ON(). ] Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | | tracing/ftrace: stop {irqs, preempt}soff tracers when tracing is stoppedFrederic Weisbecker2009-03-18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: fix a selftest warning In some cases, it's possible to see the following warning on irqsoff tracer selftest: [ 4.640003] Testing tracer irqsoff: <4>------------[ cut here ]------------ [ 4.653562] WARNING: at kernel/trace/trace.c:458 update_max_tr_single+0x9a/0xc4() [ 4.660000] Hardware name: System Product Name [ 4.660000] Modules linked in: [ 4.660000] Pid: 301, comm: kstop/1 Not tainted 2.6.29-rc8-tip #35837 [ 4.660000] Call Trace: [ 4.660000] [<4014b588>] warn_slowpath+0x79/0x8f [ 4.660000] [<402d6949>] ? put_dec+0x64/0x6b [ 4.660000] [<40162b56>] ? getnstimeofday+0x58/0xdd [ 4.660000] [<40162210>] ? clocksource_read+0x3/0xf [ 4.660000] [<4015eb44>] ? ktime_set+0x8/0x34 [ 4.660000] [<4014101a>] ? balance_runtime+0x8/0x56 [ 4.660000] [<405f6f11>] ? _spin_lock+0x3/0x10 [ 4.660000] [<4011f643>] ? ftrace_call+0x5/0x8 [ 4.660000] [<4015d0f1>] ? task_cputime_zero+0x3/0x27 [ 4.660000] [<40190ee7>] ? cpupri_set+0x90/0xcb [ 4.660000] [<405f7208>] ? _spin_lock_irqsave+0x22/0x34 [ 4.660000] [<40190f12>] ? cpupri_set+0xbb/0xcb [ 4.660000] [<405f7151>] ? _spin_unlock_irqrestore+0x23/0x35 [ 4.660000] [<4018493f>] ? ring_buffer_reset_cpu+0x27/0x51 [ 4.660000] [<405f7208>] ? _spin_lock_irqsave+0x22/0x34 [ 4.660000] [<40184962>] ? ring_buffer_reset_cpu+0x4a/0x51 [ 4.660000] [<405f7151>] ? _spin_unlock_irqrestore+0x23/0x35 [ 4.660000] [<4018cc29>] ? trace_hardirqs_off+0x1a/0x1c [ 4.660000] [<405f7151>] ? _spin_unlock_irqrestore+0x23/0x35 [ 4.660000] [<40184962>] ? ring_buffer_reset_cpu+0x4a/0x51 [ 4.660000] [<401850f3>] ? cpumask_next+0x15/0x18 [ 4.660000] [<4018a41f>] update_max_tr_single+0x9a/0xc4 [ 4.660000] [<4014e5fe>] ? exit_notify+0x16/0xf2 [ 4.660000] [<4018cd13>] check_critical_timing+0xcc/0x11e [ 4.660000] [<4014e5fe>] ? exit_notify+0x16/0xf2 [ 4.660000] [<4014e5fe>] ? exit_notify+0x16/0xf2 [ 4.660000] [<4018cdf1>] stop_critical_timing+0x8c/0x9f [ 4.660000] [<4014e5c4>] ? forget_original_parent+0xac/0xd0 [ 4.660000] [<4018ce3a>] trace_hardirqs_on+0x1a/0x1c [ 4.660000] [<4014e5c4>] forget_original_parent+0xac/0xd0 [ 4.660000] [<4014e5fe>] exit_notify+0x16/0xf2 [ 4.660000] [<4014e8a5>] do_exit+0x1cb/0x225 [ 4.660000] [<4015c72b>] ? kthread+0x0/0x69 [ 4.660000] [<4011f61d>] kernel_thread_helper+0xd/0x10 [ 4.660000] ---[ end trace a7919e7f17c0a725 ]--- [ 4.660164] .. no entries found ..FAILED! During the selftest of irqsoff tracer, we do that: /* disable interrupts for a bit */ local_irq_disable(); udelay(100); local_irq_enable(); /* stop the tracing. */ tracing_stop(); /* check both trace buffers */ ret = trace_test_buffer(tr, NULL); If a callsite performs a new max delay with irqs off just after tracing_stop, update_max_tr_single() -> ring_buffer_swap_cpu() will be called with the buffers disabled by tracing_stop(), hence the warning, then ring_buffer_swap_cpu() return -EAGAIN and update_max_tr_single() complains. Fix it by also stopping the tracer before stopping the tracing globally. A similar situation can happen with preemptoff and preemptirqsoff tracers where we apply the same fix. Reported-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1237325938-5240-1-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | | Merge branch 'tip/tracing/ftrace' of ↵Ingo Molnar2009-03-18
|\ \ \ | |/ / |/| | | | | git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-2.6-trace into tracing/ftrace
| * | tracing: make power tracer start/stop methods lighter weightSteven Rostedt2009-03-17
| | | | | | | | | | | | | | | | | | | | | The start/stop methods of a tracer should be able to be executed in all contexts. This patch converts the power tracer to do so. Signed-off-by: Steven Rostedt <srostedt@redhat.com>
| * | tracing: make sched_switch stop/start light weightSteven Rostedt2009-03-17
| | | | | | | | | | | | | | | | | | | | | | | | | | | The stopping and starting of a tracer should be light weight and be able to be called in all contexts. The sched_switch grabbed mutexes in the start/stop functions. This patch changes it to a simple variable, on/off. Signed-off-by: Steven Rostedt <srostedt@redhat.com>
| * | tracing: add global-clock option to provide cross CPU clock to tracesSteven Rostedt2009-03-17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: feature to allow better serialized clock This patch adds an option called "global-clock" that will allow the tracer to switch to a slower but more accurate (across CPUs) clock. Signed-off-by: Steven Rostedt <srostedt@redhat.com>
| * | ring-buffer: add api to allow a tracer to change clock sourceSteven Rostedt2009-03-17
| | | | | | | | | | | | | | | | | | | | | This patch adds a new function called ring_buffer_set_clock that allows a tracer to assign its own clock source to the buffer. Signed-off-by: Steven Rostedt <srostedt@redhat.com>
* | | Merge branch 'tip/tracing/ftrace' of ↵Ingo Molnar2009-03-17
|\| | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-2.6-trace into tracing/ftrace
| * | tracing: stop comm recording on tracing offSteven Rostedt2009-03-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: fix for losing comms in trace The command lines of tasks are cached at sched switch to not need to record them at every trace point. Disabling the tracing on stops the recording of traces, but does not stop the caching of command lines. When the tracing is off the cache may overflow and cause the tracing to show incorrect tasks matching the PIDs. This patch disables prevents updates to the comm cache when the ring buffer is off. Signed-off-by: Steven Rostedt <srostedt@redhat.com>
| * | tracing: protect reader of cmdline outputSteven Rostedt2009-03-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: fix to one cause of incorrect comm outputs in trace The spinlock only protected the creation of a comm <=> pid pair. But it was possible that a reader could look up a pid, and get the wrong comm because it had no locking. This also required changing trace_find_cmdline to copy the comm cache and not just send back a pointer to it. Signed-off-by: Steven Rostedt <srostedt@redhat.com>
| * | tracing/ftrace: fix the check on nopped sitesFrederic Weisbecker2009-03-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: fix a dynamic tracing failure Recently, the function and function graph tracers failed to use dynamic tracing after the following commit: fa9d13cf135efbd454453a53b6299976bea245a9 (ftrace: don't try to __ftrace_replace_code on !FTRACE_FL_CONVERTED rec) The patch is right except a mistake on the check for the FTRACE_FL_CONVERTED flag. The code patching is aborted in case of successfully nopped sites. What we want is the opposite: ignore the callsites that haven't been nopped. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Steven Rostedt <srostedt@redhat.com>
* | | tracing: fix leak in event_format_read()Tom Zanussi2009-03-17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: fix memory leak If event_format_read() exits early due to nonzero ppos, the previous kmalloc doesn't get freed - might as well do the check before the kmalloc and avoid the problem. Signed-off-by: Tom Zanussi <tzanussi@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: =?ISO-8859-1?Q?Fr=E9d=E9ric?= Weisbecker <fweisbec@gmail.com> LKML-Reference: <1237270859.8033.141.camel@charm-linux> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | | tracing/core: fix early free of cpumasksFrederic Weisbecker2009-03-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: fix crashes when tracing cpumasks While ring-buffer allocation, the cpumasks are allocated too, including the tracing cpumask and the per-cpu file mask handler. But these cpumasks are freed accidentally just after. Fix it. Reported-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> LKML-Reference: <1237164303-11476-1-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | | tracing/ftrace: fix double calls to tracing_start()Frederic Weisbecker2009-03-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: fix a warning during preemptirqsoff selftests When the preemptirqsoff selftest fails, we see the following warning: [ 6.050000] Testing tracer preemptirqsoff: .. no entries found .. ------------[ cut here ]------------ [ 6.060000] WARNING: at kernel/trace/trace.c:688 tracing_start+0x67/0xd3() [ 6.060000] Modules linked in: [ 6.060000] Pid: 1, comm: swapper Tainted: G [ 6.060000] Call Trace: [ 6.060000] [<ffffffff802460ff>] warn_slowpath+0xb1/0x100 [ 6.060000] [<ffffffff802a8f5b>] ? trace_preempt_on+0x35/0x4b [ 6.060000] [<ffffffff802a37fb>] ? tracing_start+0x31/0xd3 [ 6.060000] [<ffffffff802a37fb>] ? tracing_start+0x31/0xd3 [ 6.060000] [<ffffffff80271e0b>] ? __lock_acquired+0xe6/0x1f2 [ 6.060000] [<ffffffff802a37fb>] ? tracing_start+0x31/0xd3 [ 6.060000] [<ffffffff802a3831>] tracing_start+0x67/0xd3 [ 6.060000] [<ffffffff802a8ace>] ? irqsoff_tracer_reset+0x2d/0x57 [ 6.060000] [<ffffffff802a4d1c>] trace_selftest_startup_preemptirqsoff+0x1c8/0x1f1 [ 6.060000] [<ffffffff802a4798>] register_tracer+0x12f/0x241 [ 6.060000] [<ffffffff810250d0>] ? init_irqsoff_tracer+0x0/0x53 [ 6.060000] [<ffffffff8102510b>] init_irqsoff_tracer+0x3b/0x53 This is because in fail case, the preemptirqsoff tracer selftest calls twice the tracing_start() function: int trace_selftest_startup_preemptirqsoff(struct tracer *trace, struct trace_array *tr) { if (!ret && !count) { printk(KERN_CONT ".. no entries found .."); ret = -1; tracing_start(); <----- goto out; } [...] out: trace->reset(tr); tracing_start(); <------ tracing_max_latency = save_max; return ret; } Since it is well handled in the out path, we don't need the conditional one. Reported-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> LKML-Reference: <1237159961-7447-1-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | | tracing/core: fix missing mutex unlock on tracing_set_tracer()Frederic Weisbecker2009-03-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: fix possible locking imbalance In case of ring buffer resize failure, tracing_set_tracer forgot to release trace_types_lock. Fix it. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> LKML-Reference: <1237151439-6755-5-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | | tracing/syscalls: select kallsysmsFrederic Weisbecker2009-03-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Syscall tracing must select kallsysms. The arch code builds a table to find the syscall metadata by syscall number. It needs the syscalls names resolution from the symbol table to know which name found on the syscalls metadatas match a function pointer from the arch sys_call_table. Reported-by: Andrew Morton <akpm@linux-foundation.org> Reported-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> LKML-Reference: <1237151439-6755-4-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | | tracing/syscalls: protect thread flag toggling from racesFrederic Weisbecker2009-03-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: fix syscall tracer enable/disable race The current thread flag toggling is racy as shown in the following scenario: - task A is the last user of syscall tracing, it releases the TIF_SYSCALL_FTRACE on each tasks - at the same time task B start syscall tracing. refcount == 0 so it sets up TIF_SYSCALL_FTRACE on each tasks. The effect of the mixup is unpredictable. So this fix adds a mutex on {start,stop}_syscall_tracing(). Reported-by: Andrew Morton <akpm@linux-foundation.org> Reported-by: Ingo Molnar <mingo@elte.hu> LKML-Reference: <1237151439-6755-3-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | | tracing/syscalls: various cleanupsFrederic Weisbecker2009-03-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: cleanup - Drop unused cpu variable - Fix some errors on comments Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> LKML-Reference: <1237151439-6755-2-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | | tracing/syscalls: fix missing release of tracingFrederic Weisbecker2009-03-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: fix 'stuck' syscall tracer The syscall tracer uses a refcounter to enable several users simultaneously. But the refcounter did not behave correctly and always restored its value to 0 after calling start_syscall_tracing(). Therefore, stop_syscall_tracing() couldn't release correctly the tasks from tracing. Also the tracer forgot to reset the buffer when it is released. Drop the pointless refcount decrement on start_syscall_tracing() and reset the buffer when we release the tracer. This fixes two reported issue: - when we switch from syscall tracer to another tracer, syscall tracing continued. - incorrect use of the refcount. Reported-by: Andrew Morton <akpm@linux-foundation.org> Reported-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> LKML-Reference: <1237151439-6755-1-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| | |
| \ \
*-. \ \ Merge branches 'tracing/ftrace', 'tracing/syscalls' and 'linus' into ↵Ingo Molnar2009-03-16
|\ \ \ \ | |_|/ / |/| | / | | |/ | | | | | | | | | tracing/core Conflicts: arch/parisc/kernel/irq.c
| * | tracing/syscalls: core infrastructure for syscalls tracing, enhancementsFrederic Weisbecker2009-03-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: new feature This adds the generic support for syscalls tracing. This is currently exploited through a devoted tracer but other tracing engines can use it. (They just have to play with {start,stop}_ftrace_syscalls() and use the display callbacks unless they want to override them.) The syscalls prototypes definitions are abused here to steal some metadata informations: - syscall name, param types, param names, number of params The syscall addr is not directly saved during this definition because we don't know if its prototype is available in the namespace. But we don't really need it. The arch has just to build a function able to resolve the syscall number to its metadata struct. The current tracer prints the syscall names, parameters names and values (and their types optionally). Currently the value is a raw hex but higher level values diplaying is on my TODO list. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> LKML-Reference: <1236955332-10133-2-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | | ftrace: remove struct list_head from struct dyn_ftraceLai Jiangshan2009-03-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: save memory The struct dyn_ftrace table is very large, this patch will save about 50%. Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Steven Rostedt <srostedt@redhat.com> LKML-Reference: <49BA2C9F.8020009@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | | ftrace: use seq_readLai Jiangshan2009-03-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: cleanup VFS layer has tested the file mode, we do not need test it. Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Steven Rostedt <srostedt@redhat.com> LKML-Reference: <49BA2BAB.6010608@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | | ftrace: don't try to __ftrace_replace_code on !FTRACE_FL_CONVERTED recZhaolei2009-03-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Do __ftrace_replace_code for !FTRACE_FL_CONVERTED rec will always fail, we should ignore this rec. Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com> Cc: "Steven Rostedt ;" <rostedt@goodmis.org> LKML-Reference: <49BA2472.4060206@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | | ftrace: avoid double-free of dyn_ftraceZhaolei2009-03-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If dyn_ftrace is freed before ftrace_release(), ftrace_release() will free it again and make ftrace_free_records wrong. Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com> Cc: "Steven Rostedt ;" <rostedt@goodmis.org> LKML-Reference: <49BA23D9.1050900@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | | Merge branches 'tracing/ftrace' and 'tracing/syscalls'; commit 'v2.6.29-rc8' ↵Ingo Molnar2009-03-13
|\| | | | | | | | | | | into tracing/core
| * | tracing/ftrace: syscall tracing infrastructure, basicsFrederic Weisbecker2009-03-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Provide basic callbacks to do syscall tracing. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> LKML-Reference: <1236401580-5758-2-git-send-email-fweisbec@gmail.com> [ simplified it to a trace_printk() for now. ] Signed-off-by: Ingo Molnar <mingo@elte.hu>
generated by cgit v1.2.2 (git 2.25.0) at 2025-01-02 02:38:53 -0500